I like to think that the Mantis has become one of the staple vehicles for Halo as an anti-air and infantry.
It is good against players, light vehicles, and air vehicles, but still could be destroyed easily by tanks and wraiths, and I feel like really no other vehicle really fits that role in-game other than the mantis.
I’m not a huge fan of the Mantis on open maps like the Valhalla remake, was a bit of a beast if you didn’t have the tools to take it down.
Feel like it would work well on Fragmentation due to the narrow roads and rock formations.
Based on what we saw its unlikely unless they have a Heavies variant or one of the objective gametypes has it placed.